Integumentary System Pt. 2 Flashcards
People who produce a lot of melanin
Brown-toned people
People who have less melanin
Light-skinned (Caucasion)
What gives the skin a rosy glow?
The crimson color of oxygen-rich hemoglobin in the dermal blood flushes through the transparent cell layers above
What are cutaneous glands?
All are exocrine glands
What do exocrine glands retain?
- Their ducts
Where do exocrine glands empty their secretions?
Their secretions empty through the ducts to the epithelial surface
What glands lose their connection to the surface?
Endocrine
What are endocrine glands called and where do their secretions empty out?
- Ductless glands
- Secretions empty directly into the blood
Two types of cutaneous glands?
- Sebaceous
- Sweat
What are sebaceous glands and where are they found?
- Oil glands
- Found all over the skin except for the hands and the soles of the feet
Where do sebaceous glands empty out and where do they open up?
- Their ducts usually empty into hair follicles
- Some open directly onto the skin surface
What does sebum mean and what is it a product of?
- Seb = grease
- The product of the sebaceous glands
What is the sebum a mixture of and what is it? (3)
- A mixture of oily substances and fragmented cells
- A lubricant that keeps the skin soft and moist
- Prevents the hair from becoming brittle?
What chemical does sebum contain? What does sebum prevent?
- Sebum contains a chemical that helps kill bacteria
- Prevents the bacteria on the skin surface from invading the deeper skin surface
If a sebaceous gland becomes blocked with sebum
Whitehead
If the accumulated material of the whitehead oxidizes and dries, it darkens
Blackhead
What are sweat glands also called?
Sudoriterous glands (sudor means sweat)
How are sweat glands distributed and how many are on a person?
- Widely distributed in the skin
- More than 2.5 million per person
What are the two types of sweat glands?
- Eccrine glands
- Apocrine glands
Where are eccrine glands found and what do they produce?
- Found all over the body
- Produce sweat
What makes up sweat? (5)
- A clear secretion that is primarily water
- Some salt
- Vitamin C
- Traces of metabolic wastes (ammonia urea, uric acid)
- Lactic acid (chemical that attracts mosquitos)
Why are the eccrine glands important? What are they supplied with? What do they secrete and when?
- Important and highly efficient part of the body’s heat-regulating equipment
- Supplied with nerve ending
- Cause them to secrete sweat when the external temperature or body temperature is high
Where are apocrine glands confined to?
Largely confined to the axillary (armpit) and genital areas of the body
What are apocrine glands larger than and where do they empty out into?
- Larger than eccrine glands
- Ducts empty into hair follicles
What do the apocrine gland secretions contain?
- Fatty acids
- Proteins
- All substances present in eccrine secretions
What color are apocrine secretions and how do they smell?
- Milky or yellowish in color
- Odorless until the bacteria that live on the skin use its proteins and fats as a source of nutrition for their growth
- Then it takes on a musky and unpleasant odor
How many hairs are on the body?
Millions of hairs scattered all over the body
What are the functions of the hair? (protective) (3)
- Guarding the head against bumps
- Shielding the eyes (eyelashes)
- Helps to keep foreign particles out of the respiratory tract (nose hairs)
What is hair? What is it produced by?
Flexible epithelial structure, produced by a hair follicle
What is the root and the shaft?
- Root - the part enclosed in the follicle
- Shaft - the part projecting from the surface of the scalp or skin
What is a nail?
A nail is a scale like modification of the epidermis that corresponds to the hoof or claw of other animals
What three regions make up the nail?
- The free edge
- The nail body (visibly attached portion)
- The nail root (embedded in the skin, is living)
What is the nail bed?
The stratum basale of the epidermis that extends beneath the nail
What is the nail matrix?
Responsible for nail growth
What does it mean that nails are mostly nonliving material?
Nail cells are produced by the matrix, they become heavily keratinized and die
